2026 NPPES data Family Medicine Physician NPI 1154328052 M.D.
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DONALD GREGGAIN, M.D.

Family Medicine Physician in LEWISTON, Idaho. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
11K
Medicare Part D claims · 511 beneficiaries · Family Medicine Physician avg: 3K
Generic prescribing
89%
generic claims · 11% brand-name · higher generic rates reduce patient out-of-pocket costs
Industry payments
$124.31
2 payments · CMS Open Payments (Sunshine Act)

What the federal data shows

DONALD GREGGAIN, M.D. filed 10,764 Medicare Part D claims in 2023 as a Family Medicine Physician in LEWISTON, Idaho, prescribing 89% generic.

11K
Part D claims, 2023
89%
generic prescribing
Likely
board-certified (heuristic)

Every figure on this page comes straight from federal CMS records (NPPES, Medicare Part D, MIPS, Open Payments) — no proprietary rating or editorial opinion is applied.

DONALD GREGGAIN, M.D.'s Medicare Part D volume vs every U.S. prescriber

Total Medicare Part D claims, 2023 — across all CMS prescribers nationally

10,764 Top 2% higher than 98% of 1,370,886 prescribers

0–200: 670,926 prescribers (49%). Below this entry. 200–400: 182,923 prescribers (13%). Below this entry. 400–600: 90,619 prescribers (7%). Below this entry. 600–800: 56,224 prescribers (4%). Below this entry. 800–1,000: 40,919 prescribers (3%). Below this entry. 1,000–1,200: 31,827 prescribers (2%). Below this entry. 1,200–1,400: 26,224 prescribers (2%). Below this entry. 1,400–1,600: 21,710 prescribers (2%). Below this entry. 1,600–1,800: 19,072 prescribers (1%). Below this entry. 1,800–2,000: 16,451 prescribers (1%). Below this entry. 2,000–2,200: 213,991 prescribers (16%). This entry sits in this band. This provider 0 2K+ every Part D prescriber (claims/yr), bucketed by value

Each bar is a band; taller bars hold more prescribers. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Source CMS Medicare Part D Prescriber Public Use File · 2023

Board certification likely (heuristic — not verified)

DONALD GREGGAIN, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

What does the federal data show about DONALD GREGGAIN, M.D.?

Quality data not reported

NPI registry status

Active

Issued 07/07/2005

NPI 1154328052

Primary specialty

Family Medicine Physician

High-volume

147,640 US NPIs in this specialty

Medicare Part D claims

10,764 215% vs specialty avg

2023 prescription claims

Specialty avg: 3,418

Specialty distribution in Idaho

How Family Medicine Physician compares to other specialties among Idaho providers

Idaho providers

Family Medicine Physician share within Idaho

1. Family Medicine Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Family Medicine Physician share within Idaho

Specialty board-certification context

Estimated specialty board-certified rate — Family Medicine Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Family Medicine Physician ABMS/AOA estimate

Est. board-certified rate (Family Medicine Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Family Medicine Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

DONALD GREGGAIN, M.D. appears in the CMS NPPES registry as a Family Medicine Physician provider holding M.D. credentials at 415 6TH ST STE 3C, LEWISTON, ID, 83501, with a listed phone of (208) 750-3840. NPI 1154328052 was issued on 07/07/2005. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what GREGGAIN most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 10,764 prescription claims written by this provider, covering 511 Medicare beneficiaries and totaling roughly $903K in drug spend, split 11% brand-name and 89% generic by claim count, with an opioid prescribing rate of 9.0%. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Family Medicine Physician is a high-volume specialty nationwide, with 147,640 enrolled providers across 56 states and an average of 3,418 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

415 6TH ST STE 3C
LEWISTON, ID 83501

Provider Details

NPI 1154328052
Specialty Family Medicine Physician
Credentials M.D.
Gender Male
NPI Issued 07/07/2005

Hospital and facility affiliations

Facilities where DONALD GREGGAIN, M.D. bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

ST JOSEPH HOSPITAL LLC
LEWISTON, ID

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Industry payments received (2024) — CMS Open Payments transparency data

The federal Physician Payments Sunshine Act (part of the Affordable Care Act) requires drug and medical-device manufacturers + group purchasing organizations to publicly report payments and other transfers of value to physicians and teaching hospitals. The data below covers 2024 for DONALD GREGGAIN, M.D.. Source: openpaymentsdata.cms.gov.

Total received

$124

Largest payer

Phathom Pharmaceuticals, Inc.

Most common payment type

Food and Beverage

Industry payments are not necessarily indicators of bias — they include research funding, consulting fees for evidence-based work, royalties for inventions, food at conferences, and similar items. The disclosure exists for transparency. Read our methodology for how we interpret this data.

Brand vs generic prescribing mix · Typical

DONALD GREGGAIN, M.D. — brand share 11.0%
Specialty average (est.)

11% brand-name claims vs 89% generic, on 10,764 2023 Medicare Part D claims.

The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

10,764
Total Claims
$903K
Total Drug Cost
511
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
20,577
Total Day Supply
596,838
Brand vs Generic
11% brand / 89% generic
Brand Drug Cost
$673K
Generic Drug Cost
$227K
Opioid Claims
968 (9.0% rate)
Antibiotic Claims
258

Patient Demographics

Average Patient Age
73.6 years
Avg HCC Risk Score
1.02
Gender Split
53% female / 47% male
Age Distribution
<65: 45, 65-74: 246, 75-84: 146, 85+: 74

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

What DONALD GREGGAIN, M.D. prescribes most

Top Medicare Part D drugs by claim count, 2023

claims
Source CMS Medicare Part D Prescriber Public Use File As of 2023
Drug Claims
Hydrocodone-Acetaminophen
Hydrocodone/Acetaminophen
449
Levothyroxine Sodium
404
Atorvastatin Calcium
322
Gabapentin
267
Losartan Potassium
260
Omeprazole
235
Lisinopril
192
Trazodone Hcl
189
Amlodipine Besylate
181
Pantoprazole Sodium
172

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Family Medicine Physician Overview

How DONALD GREGGAIN, M.D. fits within the Family Medicine Physician landscape nationally.

147,640
Family Medicine Physician Providers in US
56
States with Family Medicine Physician
3,418
Avg Claims per Provider

DONALD GREGGAIN, M.D.'s 10,764 claims are above the specialty average of 3,418.

Nearby Family Medicine Physician Providers in Idaho

Other clinicians with the same primary specialty enrolled in Idaho, drawn from the same CMS NPPES roster as GREGGAIN.

Compare Family Medicine Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is DONALD GREGGAIN, M.D.'s specialty?
DONALD GREGGAIN, M.D. specializes in Family Medicine Physician and practices in LEWISTON, Idaho. Credentials: M.D..
How much does DONALD GREGGAIN, M.D. prescribe under Medicare Part D?
In 2023, DONALD GREGGAIN, M.D. wrote 10,764 Medicare Part D claims totaling $903K in drug costs for 511 beneficiaries.
Where is DONALD GREGGAIN, M.D. located?
DONALD GREGGAIN, M.D. is located at 415 6TH ST STE 3C, LEWISTON, ID, 83501. Phone: (208) 750-3840.
What is DONALD GREGGAIN, M.D.'s NPI number?
DONALD GREGGAIN, M.D.'s National Provider Identifier (NPI) is 1154328052, issued on 07/07/2005.
Does DONALD GREGGAIN, M.D. prescribe more brand-name or generic drugs?
DONALD GREGGAIN, M.D.'s prescribing is 11% brand-name and 89% generic drugs by claim count, with $673K in brand drug costs.
Does DONALD GREGGAIN, M.D. prescribe opioids?
Yes, DONALD GREGGAIN, M.D. had 968 opioid claims in 2023 with an opioid prescribing rate of 9.0%.
How many Family Medicine Physician providers are there in the US?
There are 147,640 Family Medicine Physician providers across 56 states in the US. The average Family Medicine Physician provider writes 3,418 Medicare Part D claims per year.
What drugs does DONALD GREGGAIN, M.D. prescribe most often?
Based on 2023 Medicare Part D data, DONALD GREGGAIN, M.D.'s most frequently prescribed drugs include Hydrocodone-Acetaminophen, Levothyroxine Sodium, Atorvastatin Calcium. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does DONALD GREGGAIN, M.D. accept Medicare?
DONALD GREGGAIN, M.D. appears in CMS Medicare data with 10,764 Part D claims and 511 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify DONALD GREGGAIN, M.D.'s credentials?
DONALD GREGGAIN, M.D.'s NPI is 1154328052 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology